The present invention relates to mounting DIN rail brackets without using hardware, and more particularly, to a DIN rail mounting system in which a DIN rail is mounted on brackets which are in turn secured to a surface by mating feet and posts on the bracket with their respective receiving slots and holes in the surface.
Electrical components are typically mounted to electrical panels by fastening the components to a DIN rail. A DIN rail is an elongated raised track or channel shaped strip having opposed coplanar flanges along its length and which comes in a variety of cross-sectional shapes that are designed to provide an area within which the electrical components are fixed. Mounting components on a DIN rail requires that the component being mounted have a locking mechanism and a release mechanism that typically includes a movable or flexible part which can be released from the DIN rail. U.S. Pat. No. 4,921,445 entitled xe2x80x9cRail Mounting Apparatus for Electrical Componentsxe2x80x9d discloses a rail mounting apparatus in which a spring clamp is held flexibly in position such that the clamp slides onto the rail. Other more complex mechanisms include a flexible latching member formed as an integral part of the device to be mounted and a spring-biased sliding latch which engages the DIN rail.
Generally, mounting slots or holes are cut or punched along the length of the rail to facilitate the mounting of the rail on brackets which are then mounted on a surface relative to an electrical panel. The DIN rail mounting bracket is typically an L-shaped bracket designed for attachment to a flat surface. This L-shaped bracket usually includes holes on one leg for attaching the DIN rail to the bracket and holes on the adjacent leg for attaching the bracket to the mounting surface. Presently, a very common method of securing the DIN rail to the mounting brackets is to insert bolts, screws, or rivets through the holes of the L-shaped bracket and the DIN rail thus securing the DIN rail to one leg of the bracket. The use of bolts, screws, or rivets adds the costs of the hardware to the finished product, as well as increases the costs of labor involved with bolting, screwing, or riveting the bracket into place. Other methods of securing DIN rail to a panel involve the integral molding of the rail into the casing of a circuit breaker box.
The mounting bracket is typically held to a flat surface such as an electrical panel using a plurality of bolts, screws, or rivets. As with securing the DIN rail to the bracket, the use of bolts, screw, or rivets adds to the cost of the finished product. Alternately, the mounting bracket can be secured to the flat surface by welding it in place. This method provides strong support for the bracket and DIN rail; however, it is inflexible, as the support cannot be detached and repositioned within the electrical system. Another method of securing an L-shaped bracket to a surface is disclosed in U.S. Pat. No. 5,768,091 entitled xe2x80x9cCircuit Breaker Mounting Bracketxe2x80x9d, which recites a flange depending from a base member of the bracket wherein the flange is fixably attached to the surface while a brace member rests on the surface and supports an upright member.
One problem encountered with electrical components mounted on DIN rails is that the pulling, twisting, or torque action experienced when installing or removing the components may cause the mounting brackets to be dislodged from the surface. Even electrical devices equipped with quick release mechanisms allowing for easy clamping to a DIN rail may put undue stresses on the brackets thereby causing loosening of the bolts, screws, or rivets that hold the bracket to the surface. Loose bolts, screws, or rivets may compromise the quality of the electrical system and present a hazardous condition.
In an exemplary embodiment of the invention, a bracket for mounting DIN rail has an L-shaped structure and comprises a support member having a rail mounting pin protruding outward therefrom, a hole disposed adjacent the rail mounting pin, a base member extending perpendicularly from the support member and having a bracket mounting pin and a post protruding outward from the base member, and a brace member positioned between the support member and the base member to give support to the L-shaped structure. A relief is cut laterally across the base member and extends into the brace to allow the support member and the base member to flex relative to each other.
The rail mounting pin is an oblong-shaped head positioned on the end of a shank, the head being configured and dimensioned to engage a receiving hole in the DIN rail and retain the DIN rail against the support member when the DIN rail is placed over the head and rotated through a ninety degree turn. The hole positioned adjacent the rail mounting pin is dimensioned to receive a fastener positioned therethrough and extending through a second hole in the DIN rail. Use of such a fastener prevents the axial rotation of the DIN rail on the shank when the rail mounting pin engages the receiving hole in the DIN rail.
A bracket mounting pin depends from the base member. The bracket mounting pin comprises a foot retaining pin and a retaining foot disposed on the end thereof. The foot retaining pin is dimensioned to slidably engage a slot in a surface and remain in the slot due to frictional resistance between the retaining pin and the edges of the slot. The retaining foot is dimensioned to prevent the bracket from being perpendicularly removed from the slot. A post also protrudes outward from the base member and either snappingly or frictionally engages a post hole to further assist in retaining the bracket on the surface.
Rail mounting pins, bracket mounting pins, and posts allow the DIN rail to be mounted to the L-shaped bracket and the L-shaped bracket to be mounted to a surface without utilizing hardware and tools thus avoiding the costs associated with hardware and tools. Mounting of the brackets to a surface by slidably engaging the foot with a slot and inserting a post into a post hole will enable the brackets to remain secure while supporting a DIN rail and electrical components attached thereto.